Answer: 12,620,256
Step-by-step explanation:
Given: The camera shop socks eight different types of batteries and there re at least 31 batteries of each type.
Here we want to select r= 31 batteries from n= 8 kinds of batteries, then formula we use to find number of ways is 

Hence, the number of ways can a total inventory of 31 batteries be distributed among the eight different types = 12,620,256
Do you mean the cost per ounce?
Then that would be $0.1496, or rounded to the nearest cent, 15 cents a ounce.
Answer:
a=200;110;101andb=decreasing
Step-by-step explanation:
a.(100×10+1000)/10=200
(100×100+1000)/100=110
(100×1000+1000)/1000=101
Simplified :(5x+4y)(5x−4y)
=(5x+4y)(5x+−4y)
=(5x)(5x)+(5x)(−4y)+(4y)(5x)+(4y)(−4y)
=25x2−20xy+20xy−16y2
=25x2−16y2
hope this helps!